The market for Location-Based Services (LBS) is potentially tremendous. Location-Based Services may comprise services where information about the location of users or assets may be required. One of state-of-the art technology driving the LBS market today is assisted global navigation satellite systems (AGNSS). This technology combines satellite positioning and communication networks such as mobile networks to reach performance levels allowing the wide deployment of Location-Based Services. AGNSS uses assistance data provided from an AGNSS server via, for example, a mobile telephony network, to speed up the process of acquiring a position fix especially in a weak signal environment. The AGNSS server has access to a reference network of GNSS receivers that are placed in ideal locations (direct line-of-sight to satellites). The GNSS receivers comprise Global Positioning System (GPS) receivers, the Global Orbiting Navigation Satellite System (GLONASS) receivers, and/or the GALILEO system receivers. The reference network may be used as a source for providing the assistance data. Depending on the AGNSS server and GNSS receiver capabilities, the assistance data may comprise various elements such as ephemeris data. The ephemeris data may be valid only for the visibility period of each detected satellite such as a GPS satellite, which may be approximately 4 hours assuming that the receiver is static and the GPS satellite is just rising above the horizon.
Further limitations and disadvantages of conventional and traditional approaches will become apparent to one of skill in the art, through comparison of such systems with some aspects of the present invention as set forth in the remainder of the present application with reference to the drawings.